A dependency represents a relationship between two planning elements, where one element with its start or end is dependent on the start or end of the other one. A planning element is a successor, if it is dependent on the other element. A planning element is a predecessor, if the other planning element depends on it. These two types are displayed on the project plan (Gantt chart). The dependency describes a consequence and chronological order between two elements in this chart.

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Types of dependencies

In InLoox PM, you can use the duration of planning elements, different types of dependencies, constraints and positive and negative lags. You can modify the information in the planning by using the features in the Ribbon, New / Edit dialog box and in the Gantt chart. InLoox PM automatically adjusts the schedule and displays information about the relationships between planning elements.

The type of dependency between activities defines how the activities are linked to each other. InLoox PM provides you with the following dependency types:

Dependency

Example

Description

End-to-Start

The activity B begins after the activity A is finished. E.g. the activity A is "Prepare a presentation" and the activity B is "Hold a presentation". In this case the "Hold a presentation" activity cannot begin until the "Prepare a presentation" activity is completed.

Start-to-Start

The dependent activity B cannot begin until the activity A that it depends on is completed. For example, the activity A is "Prepare texts for the web site" and the activity B is "Add screenshots". However, the "Add screenshots" activity begins, when the "Prepare texts for the web site" activity begins.

End-to-End

The activity B cannot be completed until the activity A that it depends on is completed. E.g. the activity A is "Write texts" and the activity B is "Check texts". The "Check texts" activity cannot be completed until the "Write texts" activity is finished.

Start-to-End

The activity B cannot be completed until the activity A that it depends on begins. This type is also called jump sequence. The jump sequence chain forms the latest possible project start.

E.g. the activity A is "Print a brochure" and the activity B is "Send for printing". The "Send for printing" activity must be finished before "Print a brochure" begins.

Edit a dependency in the Gantt chart

This is how you can generate and edit dependencies:

Double-click on the link line in the Gantt chart

The Edit Dependency dialog box is displayed. In the Type field select the direction of the dependency.

In the Lag field define the days and hours of the lag between two planning elements.

Activate the Negative control box for the negative lag. The description of it you will find down in the Lags area.

Lags

InLoox PM provides you with the possibility to determine the lags between two linked planning elements. By using lags, you can define the time interval between two planning elements. You can create a positive or a negative lag.

Positive lag The issue date (start or end) of the successor is after the predecessor. A positive lag means "waiting". E.g. you want to set a lag between two activities "Draw a picture" and "Frame a picture", because the paint needs to dry. Create a positive lag by putting in e.g. 2 days. The time lag of 2 days is always constant, even if the predecessor will take 4 days more.

Negative lag If an activity is supposed to start before its predecessor ends, it is necessary to define a negative lag (both activities overlap). A negative lag means "to bring forward". Example: You want to prepare a marketing brochure. Two activities are supposed to overlap so that the activity "Illustrate" starts 3 days before the activity "Write texts" is completed.

See the upper section Edit dependencies in the Gantt chart in ordder to know how you can edit lags.

Constraints

Use constraints for each activity in order to control the start and end date. InLoox PM provides you with the constraint types you see in the list below. For new planning elements, the constraint As soon as possible is set up as default value for the forward scheduling and As late as possible for the backward scheduling.

You can combine the different constraint types with the different types of dependencies.

Constraint type

Description

As soon as possible

An activity begins as early as possible. This activity is calculated from the start date.

As late as possible

An activity begins as late as possible. This activity is calculated from the end date.

End no later than

An activity will be finished on or before a specified date. Use this constraint to ensure that an activity does not finish after a certain date.

Start no later than

An activity starts on or before a specified date. Use this constraint to ensure that an activity does not start after a certain date.

End no earlier than

An activity will be finished on or after a specified date. Use this constraint to ensure that an activity does not finish before a certain date.

Start no earlier than

An activity starts on or after a specified date. Use this constraint to ensure that an activity does not start before a certain date.

Start on

An activity starts on a specified date. Sets the early and the late start date to the date that you choose and anchors the activity in the schedule.

End on

An activity will be finished on a specified date. Sets the early and the late end date to the date that you choose and anchors the activity in the schedule.